Honda Prelude S 1992 - 1992 ENGINE PERFORMANCE Self-Diagnostics

Honda Prelude S 1992 - INTRODUCTION

If no faults were found while performing BASIC TESTING article in the ENGINE PERFORMANCE Section, proceed with self-diagnostics. If no trouble codes or only pass codes are present after entering self-diagnostics, proceed to TESTS W/O CODES article in the ENGINE PERFORMANCE Section for diagnosis by symptom (i.e., ROUGH IDLE, NO START, etc.).

Honda Prelude S 1992 - SELF-DIAGNOSTIC SYSTEM HARD FAILURES

Hard failures cause CHECK ENGINE light to illuminate and remain on until problem is repaired. If light comes on and remains on (light may flash) during vehicle operation, cause of malfunction must be determined using TROUBLE CODE IDENTIFICATION CHART . If a sensor fails, control unit will use a substitute value in its calculations to continue engine operation. In this condition, commonly known as limp-in mode, the vehicle runs but driveability will not be optimum.

Honda Prelude S 1992 - INTERMITTENT FAILURES

Intermittent failures may cause CHECK ENGINE light to flicker or illuminate and go out after the intermittent fault goes away. However, the corresponding trouble code will be retained in ECU memory. If related fault does not reoccur within 50 starter operations, related trouble code will be erased from control unit memory. Intermittent failures may be caused by sensor, connector or wiring related problems. See INTERMITTENTS in TESTS W/O CODES article in the ENGINE PERFORMANCE Section.

Honda Prelude S 1992 - CHECK ENGINE LIGHT

All models are equipped with a CHECK ENGINE light. As a bulb check, light illuminates when ignition is on and engine is not running. CHECK ENGINE light also illuminates when a system failure has been detected and a corresponding trouble code has been set in ECU memory. Not all trouble codes will activate CHECK ENGINE light. If CHECK ENGINE light is on and no codes are in memory, see TESTS W/O CODES article in the ENGINE PERFORMANCE Section.

Honda Prelude S 1992 - RETRIEVING CODES

With ignition off, insert jumper wire in service check connector terminal, located near center console on. See Fig. 1 . Turn ignition on and count flashes on CHECK ENGINE light.

See TROUBLE CODE IDENTIFICATION CHART table and proceed to appropriate TROUBLE CODE CHART for testing. All voltage tests should be performed with a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance, unless specifically stated differently in testing procedures.

Fig. 1: Honda Prelude S 1992 - Component Locations - Locating Service Check Connectors

Honda Prelude S 1992 - TROUBLE CODE DEFINITION

Honda Prelude S 1992 TROUBLE CODE IDENTIFICATION CHART

Code (1)	System Affected	Probable Cause
0	ECU	No Signal To ECU
1	O2 Sensor	Problem In O2 Sensor Circuit
3	MAP Sensor	Electrical Problem In MAP Sensor
4	Crank Angle Sensor (CRANK)	Open Or Shorted Signal Circuit
5	MAP Sensor	Mechanical Problem In MAP Sensor
6	Coolant Temp. (TW) Sensor	Open Or Shorted Signal Circuit
7	Throttle Angle Sensor	Open Or Shorted Signal Circuit
8	Crank Angle Sensor (TDC)	Open Or Shorted Signal Circuit
9	Crank Angle Sensor (CYL)	Open Or Shorted Signal Circuit
10	Intake Air Temperature	Problem With Sensor
12	EGR System	No EGR action
13	Atmospheric Pressure (PA)	Problem with PA Circuit
14	Electronic Air Control Valve (EACV)	Open Or Shorted Signal Circuit
15	Ignition Output Signal	Electrical Problem In Signal Circuit
16	Fuel Injector	Problem In Fuel Injector Circuit
17	Vehicle Speed Sensor (VSS)	Open Or Shorted Signal Circuit
20	Electrical Load Detector	Problem With Electrical Load Detector Circuit
23	Knock Sensor	Problem With Knock Sensor Circuit
30	A/T FI Signal A	Problem In A/T Control Unit And ECU Circuit
31	A/T FI Signal B	Problem In A/T Control Unit And ECU Circuit
41	O2 Sensor Heater	Problem With O2 Sensor Circuit
43	Fuel Supply System	Problem With O2 Sensor Circuit Or Fuel System
(1) If codes other than these are indicated, repeat self-diagnosis. If code(s) reappear, substitute a known good ECU, and recheck codes. If code(s) clear, replace ECU.

Honda Prelude S 1992 - ECU RESET PROCEDURE/CLEARING CODES

To reset ECU, remove BACK UP fuse (CLOCK/RADIO fuse on Prelude) from underhood fuse/relay block. Leave fuse out for 10 seconds to reset ECU. This procedure cancels clock and radio settings, make note of settings before beginning reset procedure.

NOTE:

Some models have an anti-theft code built into the radio circuit. After ECU reset, the radio will not function until code is entered.

Honda Prelude S 1992 - ECU LOCATION

ECU is located under carpet in passenger-side footwell. See Fig. 1 .

Honda Prelude S 1992 - SUMMARY

If no hard trouble codes (or only pass codes) are present, driveability symptoms exist or intermittent codes exist, proceed to TESTS W/O CODES article in the ENGINE PERFORMANCE Section for diagnosis by symptom (i.e., ROUGH IDLE, NO START, etc.) or intermittent diagnosis procedures.

Honda Prelude S 1992 - TROUBLE CODE CHARTS

NOTE:

In the following trouble code charts, illustrations and schematics are courtesy of American Honda Motor Co., Inc.

Honda Prelude S 1992 - USING TROUBLE CODE CHARTS

To use TROUBLE CODE CHARTS, see RETRIEVING CODES under SELF-DIAGNOSTIC SYSTEM. After codes have been recorded, proceed to appropriate TROUBLE CODE CHART.

When directed by chart to install ECU test harness, turn ignition off. Connect ECU Test Harness (07LAJ-PT3010A ) between ECU and connector. See Fig. 2 . Follow code chart directions.

If CHECK ENGINE light fails to light when ignition switch is turned on, proceed to NO CODE, NO CHECK ENGINE LIGHT chart for appropriate vehicle.

If check engine light stays on for more than 2 seconds after ignition switch is turned on, proceed to CODE/NO CODE, CHECK ENGINE LIGHT STAYS ON chart for appropriate vehicle.

Fig. 2: Honda Prelude S 1992 - Component Locations - Installing PGM-FI ECU Test Harness & Identifying Terminals

Honda Prelude S 1992 - NO CODE - NO CHECK ENGINE LIGHT

Fig. 3: Honda Prelude S 1992 - Component Locations - No Code Chart - No Check Engine Light

Honda Prelude S 1992 - CODE/NO CODE - CHECK ENGINE LIGHT STAYS ON

Fig. 4: Honda Prelude S 1992 - Component Locations - Code/No Code Chart (1 Of 3) - Check Engine Light Stays On

Fig. 5: Honda Prelude S 1992 - Component Locations - Code/No Code Chart (2 Of 3) - Check Engine Light Stays On

Fig. 6: Honda Prelude S 1992 - Component Locations - Code/No Code Chart (3 Of 3) - Check Engine Light Stays On

Honda Prelude S 1992 - CODE 1 - OXYGEN SENSOR CIRCUIT

Fig. 7: Honda Prelude S 1992 - Component Locations - Code 1 Chart - Oxygen Sensor Circuit

Honda Prelude S 1992 - CODE 3 - MAP SENSOR CIRCUIT

Fig. 8: Honda Prelude S 1992 - Component Locations - Code 3 Chart (1 Of 2) - Map Sensor Circuit

Fig. 9: Honda Prelude S 1992 - Component Locations - Code 3 Chart (2 Of 2) - Map Sensor Circuit

Honda Prelude S 1992 - CODES 4, 8 & 9 - TDC/CRANK/CYL SENSOR CIRCUITS

Fig. 10: Honda Prelude S 1992 - Component Locations - Codes 4, 8 & 9 Chart (1 Of 2) TDC/CRANK/CYL Sensor CKT.

Fig. 11: Honda Prelude S 1992 - Component Locations - Codes 4, 8 & 9 Chart (2 Of 2) TDC/CRANK/CYL Sensor CKT.

Honda Prelude S 1992 - CODE 5 - MAP SENSOR (MECHANICAL)

Fig. 12: Honda Prelude S 1992 - Component Locations - Code 5 Chart (1 Of 2) - MAP Sensor (Mechanical)

Fig. 13: Honda Prelude S 1992 - Component Locations - Code 5 Chart (2 Of 2) - MAP Sensor (Mechanical)

Honda Prelude S 1992 - CODE 6 - COOLANT TEMPERATURE (TW) SENSOR CIRCUIT

Fig. 14: Honda Prelude S 1992 - Component Locations - Code 6 Chart (1 Of 2) Coolant Temp. (TW) Sensor CKT.

Fig. 15: Honda Prelude S 1992 - Component Locations - Code 6 Chart (1 Of 2) Coolant Temp. (TW) Sensor CKT.

Honda Prelude S 1992 - CODE 7 - THROTTLE ANGLE SENSOR CIRCUIT

Fig. 16: Honda Prelude S 1992 - Component Locations - Code 7 Chart (1 Of 2) - Throttle Angle Sensor CKT.

Fig. 17: Honda Prelude S 1992 - Component Locations - Code 7 Chart (2 Of 2) - Throttle Angle Sensor CKT.

Honda Prelude S 1992 - CODE 10 - AIR TEMPERATURE (TA) SENSOR CIRCUIT

Fig. 18: Honda Prelude S 1992 - Component Locations - Code 10 Chart (1 Of 2) - Air Temperature (TA) Sensor CKT.

Fig. 19: Honda Prelude S 1992 - Component Locations - Code 10 Chart (2 Of 2) - Air Temperature (TA) Sensor CKT.

Honda Prelude S 1992 - CODE 12 - EXHAUST GAS RECIRCULATION (EGR) SYSTEM

Fig. 20: Honda Prelude S 1992 - Component Locations - Code 12 Chart (1 Of 4) - Exhaust Gas Recirculation (EGR) System

Fig. 21: Honda Prelude S 1992 - Component Locations - Code 12 Chart (2 Of 4) - Exhaust Gas Recirculation (EGR) System

Fig. 22: Honda Prelude S 1992 - Component Locations - Code 12 Chart (3 Of 4) - Exhaust Gas Recirculation (EGR) System

Fig. 23: Honda Prelude S 1992 - Component Locations - Code 12 Chart (4 Of 4) - Exhaust Gas Recirculation (EGR) System

Honda Prelude S 1992 - CODE 13 - ATMOSPHERIC PRESSURE (PA) SENSOR

Fig. 24: Honda Prelude S 1992 - Component Locations - Code 13 Chart - Atmospheric Pressure (PA) Sensor

Honda Prelude S 1992 - CODE 14 - ELECTRIC AIR CONTROL VALVE (EACV) SYSTEM

Fig. 25: Honda Prelude S 1992 - Component Locations - Code 14 Chart - (1 Of 2) Electric Air Control Valve (EACV) System

Fig. 26: Honda Prelude S 1992 - Component Locations - Code 14 Chart - (2 Of 2) Electric Air Control Valve (EACV) System

Honda Prelude S 1992 - CODE 15 - IGNITION OUTPUT SIGNAL

Fig. 27: Honda Prelude S 1992 - Component Locations - Code 15 Chart (1 Of 2) - Ignition Output Signal

Fig. 28: Honda Prelude S 1992 - Component Locations - Code 15 Chart (2 Of 2) - Ignition Output Signal

Honda Prelude S 1992 - CODE 16 - INJECTOR CIRCUIT

Fig. 29: Honda Prelude S 1992 - Component Locations - Code 16 Chart (1 Of 2) - Injector Circuit

Fig. 30: Honda Prelude S 1992 - Component Locations - Code 16 Chart (2 Of 2) - Injector Circuit

Honda Prelude S 1992 - CODE 17 - VEHICLE SPEED SENSOR (VSS) CIRCUIT

Fig. 31: Honda Prelude S 1992 - Component Locations - Code 17 Chart (1 Of 2) - Vehicle Speed Sensor (VSS) CKT.

Fig. 32: Honda Prelude S 1992 - Component Locations - Code 17 Chart (2 Of 2) - Vehicle Speed Sensor (VSS) CKT.

Honda Prelude S 1992 - CODE 20 - ELECTRICAL LOAD DETECTOR (ELD) CIRCUIT

Fig. 33: Honda Prelude S 1992 - Component Locations - Code 20 Chart (1 Of 2) - Electrical Load Detector (ELD) CKT.

Fig. 34: Honda Prelude S 1992 - Component Locations - Code 20 Chart (2 Of 2) - Electrical Load Detector (ELD) CKT.

Honda Prelude S 1992 - CODE 23 - KNOCK SENSOR CIRCUIT

Fig. 35: Honda Prelude S 1992 - Component Locations - Code 23 Chart (1 Of 2) - Knock Sensor Circuit

Fig. 36: Honda Prelude S 1992 - Component Locations - Code 23 Chart (2 Of 2) - Knock Sensor Circuit

Honda Prelude S 1992 - CODES 30 & 31 - A/T "A" & "B" SIGNAL CIRCUITS

Fig. 37: Honda Prelude S 1992 - Component Locations - Codes Chart 30 & 31 - A/T "A" & "B" Signal Circuits

Honda Prelude S 1992 - CODE 41 - OXYGEN SENSOR HEATER CIRCUIT

Fig. 38: Honda Prelude S 1992 - Component Locations - Code 41 Chart (1 OF 3) - Oxygen Sensor Heater CKT.

Fig. 39: Honda Prelude S 1992 - Component Locations - Code 41 Chart (2 OF 3) - Oxygen Sensor Heater CKT.

Fig. 40: Honda Prelude S 1992 - Component Locations - Code 41 Chart (3 OF 3) - Oxygen Sensor Heater CKT.

Honda Prelude S 1992 - CODE 43 - FUEL SUPPLY SYSTEM

Fig. 41: Honda Prelude S 1992 - Component Locations - Code 43 Chart (1 Of 2) - Fuel Supply System

Fig. 42: Honda Prelude S 1992 - Component Locations - Code 43 Chart (2 Of 2) - Fuel Supply System